Anorexia Nervosa

Question 1

Types of anorexia

Answer 1

• restricting = during last 3 mo no episodes of binge-eating or purging
• binge-eating/ purging type = in last 3 mo have participated in recurrent episodes of binge-eating/purging

Question 2

Severity of anorexia

Answer 2

• mild = BMI >17 kg/m
• moderate = BMI 16-16.99 kg/m2
• severe = BMI 15-15.99 kg/m2
• extreme = BMI <15 kg/m2

Question 3

Clinical features of anorexia

Answer 3

• Eating
  
  • Disordered eating
  • Don’t want to maintain weight - continue to lose weight (cf. bulimia who purge to stop getting fat - maintain weight)
  • Excessive exercising
  • Purging
  • Anhedonia - reduced response to reward makes it hard to treat
• Medical
  
  • Amenorrhoea
  • Osteopaenia/porosis +/- fracture Hx
  • Cold intolerance
  • Constipation
  • Cramps (Mg deficiency)
  • Easy bleeding (Mg deficiency)
  • Cardiac related symptoms
• Perfectionistic - obsessive compulsive personality disorder common
• Rigid thinking/cognitive inflexibility - makes treatment hard
• Alexithymia - inability to describe emotions or feelings within ones self
• Low self esteem

Question 4

Examination of anorexia: findings

Answer 4

• At any time - signs of self harm
• General inspection
  • Emaciation
  • Psychomotor retardation
  • Hypercarotinaemia (liver can’t function)
• Vitals
  • Autonomic dysfunction: hypothermia, hypotension, pulse
  • Hyperventilation (from metabolic acidosis)
• Hands
  • Lanugo hair-type - fine, soft hair
  • Alopecia
  • Russell’s signs - callouses around hands as pts often put hands into mouth to initiate purging
  • Nail changes
  • Dry skin
  • Bruises
• Eyes
  • Anaemia
  • Jaundice
• Mouth
  • Dentition - teeth erosion, gum recession
  • Tongue e.g. B12 deficiency
  • Angular stomatitis e.g. B12, iron
  • Dry mucous membranes
  • Parotid enlargement - recurrent vomiting
• CV**
  • Auscultate for systolic murmur - can get MVP
• Chest
  • Breast atrophy
• Abdo
  • Palpation - more for tenderness (if vomiting, can get gastritis)
• Legs
  • Peripheral oedema**
  • Proximal myopathy (squat)
  • Peripheral neuropathy
• Other
  • Signs of deliberate self-harm, Fractures

Question 5

What Ix might you order for anorexia?

Answer 5

• ECG: if hypokalaemic, widespread U waves, QTC 450
• UECs usually normal
  • Hypokalaemia (2.4) if vomiting/laxatives
  • HCO3 >30 mmol/L where there is vomiting or <18 in laxative misuse.
  • Urea usu. low in restricting but may be increased if dehydrated
  • Hypomagnesemia (0.74)
  • Hyponatremia (consider if patient water loading)
• Endocrine
  • Hypothalamus shuts down and goes out of wack: change in LHRH, LH, FSH, oestrogen, progesterone, T3, fasting growth hormone
  • Increased cortisol
• LFTs: AST, ALP, GGT

- Haematological:often get a pancytopenia
	• Hb (normochromic, normocytic)
	• WCC
	• Plt
	• ESR

Question 6

Medical reasons (not psychiatric) for admission in paeds

Answer 6

• Rapid weight loss
• HR < 50 min;
• BP < 80/50 mm;

• Proximal myopathy (how would you demonstrate this to a parent?)
• Hypoglycaemia
• Electrolyte imbalance (low K, Mg, PO4)
• Several days of no oral intake
• Petechial rash and platelet suppression
Impaired cognition

Question 7

Why are CV parameters so important in anorexia?

Answer 7

because a) cardiogenic shock b) more easily slip into arrhythmia c) can get complications e.g. pericardial effusions d) injuries - falls

Question 8

Mx principles of admission of anorexia

Answer 8

• Re-feeding [primary purpose ofinpatient admission]
  
  • • supplemental phosphorus
• Keep checking bloods daily esp in first week for refeeding syndrome
• agree on target body weight on admission and reassure this weight will not be surpassed
• monitor for complications of AN

Question 9

Briefly explain how re-feeding syndrome occurs

Answer 9

• Increased CHO intake -> increased insulin for inc glyocogen, protein and fat synthesis -> PO4, K, Mg drawn into cells -> fall in serum concentration
• -> severe fluid shifts and electrolyte levels -> hypoglycaemia, hypoPO4, hyponatraemia, sometimes thiamine def

Question 10

Complications of re-feeding syndrome

Answer 10

• Peripheral: oedema, fibrillations, rhabdomyolysis
• Respiratory, pulmonary oedema, respiratory failure
• Cardiac: cardiac failure, arrhythmias
• Neurological: delirium, seizures, muscle weakness
• Haematological: anaemia
• Sx of thiamine deficiency

Question 11

General Mx options for anorexia

Answer 11

• Education for family and patient
• Refer to AMHS
○ Education/work path
○ Social connection
• Family therapy - best in adolescence, not CBT
• Nutritional rehabilitation and dietary changes
• Psychotherapy
• MDT: dietician, GP, eating disorders specialist